Warn about the impact of cache-size on performance.
diff --git a/man/dnsmasq.8 b/man/dnsmasq.8
index c7e6c88..3445f37 100644
--- a/man/dnsmasq.8
+++ b/man/dnsmasq.8
@@ -692,7 +692,7 @@
.TP
.B \-c, --cache-size=<cachesize>
-Set the size of dnsmasq's cache. The default is 150 names. Setting the cache size to zero disables caching.
+Set the size of dnsmasq's cache. The default is 150 names. Setting the cache size to zero disables caching. Note: huge cache size impacts performance.
.TP
.B \-N, --no-negcache
Disable negative caching. Negative caching allows dnsmasq to remember